Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/18—Preparation of carboxylic acid esters by conversion of a group containing nitrogen into an ester group
  • C07C67/20—Preparation of carboxylic acid esters by conversion of a group containing nitrogen into an ester group from amides or lactams
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C231/00—Preparation of carboxylic acid amides

Definitions

• the present invention relates to a process for efficient production of carboxylic acid esters and formamide by reacting carboxylic acid amides and formic acid esters, or by reacting arboxylic acid amides, alcohols, and carbon monoxide.
• Carboxylic acid esters are industrially important compounds.
• methods of producing carboxylic acid esters from carboxylic acid amides (1) a method of producing methyl acetate from acetic acid amide, (2) a method of producing methyl methacrylate from methacrylic acid amide, (3) a method of producing methyl acrylate from acrylic acid amide, and (4) a method of producing methyl ⁇ -hydroxyisobutyrate from ⁇ -hydroxyisobutyric acid amide are known.
• Formamide is used as a solvent, a treating agent, an electrolyte, or an antifreezing agent, or as an intermediate for production of dyes, pigments, medicines and so on. Moreover formamide is an important basic chemical compound which can be used also as a starting material for production of hydrogen cyanide.
• Japanese Patent Application Laid-Open Nos. 55444/1983 and 78937/1985 disclose a method of producing carboxylic acid ester and formamide by reacting carboxylic acid amide and formic acid ester in the presence of a catalyst comprising an organic or inorganic acid metal salt, or a metal carbonyl compound, and a nitrogen or phosphorus-containing organic compound.
• An object of the present invention is to provide a process for producing carboxylic acid esters and formamide from carboxylic acid amides and formic acid esters with high efficiency under mild conditions.
• Another object of the present invention is to provide a highly efficient process for producing carboxylic acid esters and formamide at a low production cost using an inexpensive apparatus instead of an expensive corrosion-resistant apparatus.
• the present invention provides a process for production of carboxylic acid esters and formamide by reacting carboxylic acid amides and formic acid esters or by reacting carboxylic acid amide, alcohols and carbon monoxide in the presence of dehydrated condensates of carboxylic acid amide with alkali metal hydroxide or with alkaline earth metal hydroxide.
• Carboxylic acid amides to be used in the present invention include aliphatic or aromatic carboxylic acid amides, ⁇ -hydroxycarboxylic acid, and ⁇ -aminocarboxylic acid amides. These amides can be prepared by subjecting nitriles to hydration, or by reacting amines and carbon monoxide. Specific examples are acetamide, lactic acid amide, acrylic acid amide, methacrylic acid amide, ⁇ -hydroxyisobutyric acid amide, benzamide, and alanineamide.
• Alcohols to be used in the present invention are preferably aliphatic alcohols having 1 to 10 carbon atoms.
• Formic acid esters are preferably esters of the above alcohols and formic acid.
• Specific examples of the aliphatic alcohols are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and 1-pentanol.
• Specific examples of formic acid esters are methyl formate, ethyl formate, propyl formate, isopropyl formate, n-butyl formate, sec-butyl formate, and n-pentyl formate.
• Dehydrated condensates of carboxylic acid amide and alkali metal hydroxide or alkaline earth metal hydroxide to be used in the process of the present invention can be easily prepared by mixing carboxylic acid amide with alkali metal hydroxide or with alkaline earth metal hydroxide and then heating the resulting mixture to remove water therefrom.
• Alkali metal hydroxide include hydroxides of lithium, sodium, potassium, rubidium or cesium, and sodium hydroxide is economically preferable.
• Alkaline earth metal hydroxides include hydroxides of magnesium, calcium, strontium or barium.
• a polar solvent e.g., alcohols
• an alcohol corresponding to the formic acid ester is particularly preferred.
• the alcohol is used in an excess amount so that it can also function as a solvent for carboxylic acid amide.
• the amount of the formic acid ester used is 0.5 to 20 mol, preferably 1.5 to 8 mol per mol of the carboxylic acid amide.
• the amount of formic acid ester is under the range, the conversion of carboxylic acid amide becomes low. On the other hand, if the amount is above the range, the amount of unreacted formic acid ester undesirably increases, which is not suitable for practical use.
• the amount of the alcohol used is 1 to 30 mol, preferably 3 to 20 mol per mol of the carboxylic acid amide.
• carboxylic acid amide can be reacted with formic acid ester, alcohol and carbon monoxide.
• the amounts of formic acid ester and alcohol used are 0.5 to 15 mol and 0.5 to 30 mol, preferably 1 to 8 mol and 2 to 15 mol, respectively, per mol of carboxylic acid amide.
• Dehydrated condensates of carboxylic acid amide with alkali metal hydroxide or with alkaline earth metal hydroxide can be usually prepared by using carboxylic acid amide in an excess amount. That is, said dehydrated condensate can be produced by mixing alkali metal hydroxide or alkaline earth metal hydroxide with carboxylic acid amide in the range of 0.001 to 0.8 mol, preferably 0.005 to 0.5 mol of the hydroxide, per mol of the carboxylic acid amide, and heating the resulting mixture, and then dehydrating under atmospheric pressure or under reduced pressure, at a temperature of 50° to 200° C., preferably 80° to 150° C.
• the amounts of alkali metal hydroxides or alkaline earth metal hydroxides are usually 0.001 to 0.3 mol, preferably 0.003 to 0.1 mol, per mol of carboxylic acid amide. That is, if the above range is satisfied, dehydrated condensates prepared in the reaction system where carboxylic acid amide is excessive, may be used as they are. Or said dehydrated condensates may be used after adjusting to the desired proportion of the amount by adding carboxylic acid amide again.
• Carboxylic acid amide in the present invention may be used singly or in a mixture of two kinds or more. Further, carboxylic acid amides for preparation of dehydrated condensates may be identical to or different form carboxylic acid amide for reaction with formic acid ester.
• the reaction temperature and period of time can be chosen from a wide range depending on the kind of the starting material, the amount of the catalyst charged, and the desired conversion.
• the reaction temperature is preferably 0° to 200° C. and more preferably 20° to 150° C. If the reaction temperature is less than 0° C., a rate of reaction is too low for practical use, and if it is more than 200° C., decomposition of formamide and deactivation of the catalyst undesirably occur.
• the reaction period of time is preferably 0.1 to 20 hours and more preferably 0.2 to 10 hours.
• reaction pressure should be between atmospheric pressure and 300 atm, and from an economic standpoint, it is preferably between atmospheric pressure and 100 atm.
• reaction pressure is in a range of 10 to 500 atm, preferably 30 to 200 atm as a partial pressure of carbon monoxide.
• the process of the present invention can be carried out batchwise or continuously. Industrially a continuous process is preferred.
• carboxylic acid esters and formamide can be produced with high selectivity under mild reaction conditions from carboxylic acid amides and formic acid esters by the use of dehydrated condensates of carboxylic acid amide with alkali metal hydroxide or with alkaline earth metal hydroxide as a catalyst.
• the process of the present invention is of great significance from an industrial standpoint, since the catalysts used are inexpensive.
• the solution was transferred into a 120-ml stainless steel autoclave, and 12.6 g (0.21 mol) of methyl formate was added, and the mixture was reacted at 60° C. for 2 hours.
• the autoclave was cooled to 10° C., and then the product was taken out thereof and was subjected to a gas chromatographic analysis.
• the selectivity into formamide (based on the reacted ⁇ -hydroxyisobutyric acid amide) was 99.5%.
• the autoclave was cooled to 10° C., and then the product was taken out and was subjected to a gas chromatographic analysis.
• the autoclave was cooled to 10° C., and then the content was taken out and was subjected to a gas chromatographic analysis.
• Example 2 The same procedure of Example 1 was repeated with the exception that 5.9 g (0.1 mol) of acetamide was used as the carboxylic acid amide.
• Example 2 The same procedure of Example 1 was repeated with the exception that 8.5 g (0.1 mol) of methacrylic acid amide was used as the carboxylic acid amide and the resulting water was distilled away at 30 torr for 10 minutes.
• Example 2 The same procedure of Example 1 was repeated with the exception that 12.2 g (0.1 mol) of nicotinic acid amide was used as the carboxylic acid amide.
• the conversion of nicotinic acid amide was 71.8%, and the selectivity into methyl nicotinate was 96.6%.
• the selectivity into formamide was 97.6%.
• the conversion of ⁇ -hydroxyisobutyric acid amide was 70.6% and the selectivity into methyl ⁇ -hydroxyisobutyrate was 98.1%.
• the selectivity into formamide was 96.0%.
• Example 2 The same procedure was carried out as in Example 1 with the exception that 51 g (0.5 mol) of butyl formate was used in place of methyl formate and 22.2 g (0.3 mol) of butanol was used in place of methanol.
• Example 2 The same procedure was carried out as in Example 1 with the exception that 0.28 g (0.005 mol) of potassium hydroxide was used in place of sodium hydroxide.
• the conversion of ⁇ -hydroxyisobutyric acid amide was 64.6% and the selectivity into methyl ⁇ -hydroxyisobutyrate was 98.6%.
• the selectivity into formamide was 99.5%.
• Example 2 The same procedure was carried out as in Example 1 with the exception that 1.71 g (0.01 mol) of barium hydroxide was used in place of sodium hydroxide.
• Example 2 In the same 3-necked flask as used in Example 1, 5.2 g (0.05 mol) of ⁇ -hydroxyisobutyric acid amide was placed and 0.08 g (0.002 mol) of powdery sodium hydroxide was added thereto, and the mixture was heated and stirred at 120° C. for 1.5 hours, to distill away the resulting water.
• the autoclave was cooled to 10° C. After the internal pressure was gradually reduced to atmospheric pressure, the product was taken out and subjected to analysis.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Pyridine Compounds (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=16162158

Family Applications (1)

Country Status (6)

Cited By (3)

Citations (4)

Family Cites Families (1)

• 1989
  • 1989-07-18 JP JP1184948A patent/JP2754763B2/ja not_active Expired - Lifetime
• 1990
  • 1990-06-08 US US07/535,751 patent/US5194668A/en not_active Expired - Lifetime
  • 1990-07-13 DE DE69007706T patent/DE69007706T2/de not_active Expired - Lifetime
  • 1990-07-13 ES ES90113406T patent/ES2054169T3/es not_active Expired - Lifetime
  • 1990-07-13 EP EP90113406A patent/EP0413140B1/en not_active Expired - Lifetime
  • 1990-07-18 KR KR1019900011054A patent/KR960006545B1/ko not_active IP Right Cessation

Patent Citations (5)

Non-Patent Citations (4)

Also Published As

Similar Documents

Legal Events